Odd fossil found in Mississippi gravel is ‘a needle in a haystack’ from the Ice Age

An odd rock found in central Mississippi is rewriting the state’s Ice Age history — and even calling into question some long-held scientific assumptions.

It’s a piece of petrified wood, but that’s not what has geologists excited.

Closer inspection has revealed the fossil is much, much older than the soil that surrounded it, state geologists say, perhaps by millions of years.

It’s almost as if someone brought an already ancient fossil to Mississippi, dug a deep hole and buried it for several hundred thousand years.

How did it get there?

It was carried, or rather, “bulldozed,” according to James Starnes, director of surface geology for the Mississippi Office of Geology.

He came to that conclusion after observing the stone’s surface, which he says proves it was dragged hundreds, if not thousands, of miles on the underside of a glacier.

This bit of rock found in central Mississippi is the first of its kind in the state: A piece of petrified wood tied to glaciers.
This bit of rock found in central Mississippi is the first of its kind in the state: A piece of petrified wood tied to glaciers.

“Nobody thinks about Mississippi and glacial ice in the same sentence. Not even most scientists. We are literally just figuring out the details of this time with these clues,” Starnes told McClatchy News.

“It was always thought that the petrified wood in Mississippi was wood that was deposited with gravel and then fossilized, so it has to be the same age as the gravel,” he says. “The fact (this fossil) is faceted proves it was fossilized well before it was dragged under the glacier and then brought to Mississippi. That makes it much older than that deposits it was found in.”

Questions are now piling up about the fossil, including its age, what kind of tree it was, where it’s from and when it was dropped in Mississippi.

However, Starnes says the most important question is if this discovery means scientists have been mistaken to use petrified wood from gravel deposits to study past environments.

Mississippi’s glacial past

There were no glaciers that came as far south as Mississippi.

Instead, the Mississippi River served as a giant drainage ditch as far back as 700,000 years ago for glaciers throughout the Pleistocene Age, experts say. The river was 200 feet higher than it is now and ran up to 15 miles east of its current location, based on the placements of gravel deposits.

These deposits — some of which are 100-feet thick — were literally the bottom of the Mississippi River during the Ice Age.

During the era, the river was the volatile centerpiece of a treacherous landscape, Starnes says.

“This included catastrophic ice-dam breaks and ice-burgs flowing down to the Gulf of Mexico,” he says. “Megafloods from glacial meltwaters and ice-dam breaks entering the Mississippi River Valley were commonplace, as it drained a sheet of ice over a mile thick into the Gulf of Mexico. The river carried with it a flood of materials bulldozed by ice.”

It was amid that debris the fossil wood found its way to the Magnolia State, perhaps scraped from some valley floor thousands of miles to the north.

‘Needle in a haystack’

Starnes likens the discovery of the petrified wood to “finding a needle in a haystack.”

The stone was found by state survey geologist Jonathan Leard a month ago, in a “massive” gravel deposit near the Hinds/Warren county line, Starnes says. The site also holds giant boulders, some weighing more than a ton, that were pushed south — or “ice rafted” — by violent glacial flooding, he says.

Some of the boulders are now on display outside the Mississippi Museum of Natural Science.

The piece of faceted fossil wood — the first of its type found in the state — is also at the museum, as part of a research collection, he says.

“The few studies done on the petrified wood (found in state gravel deposits) have been used to reconstruct ideas of the environment when they were deposited. But this wood was petrified long before it was dragged underneath a glacier, which tells us it was from an even more ancient environment,” Starnes says.

“Any past assumptions based on the studies of petrified wood from these deposits now has to be called into question. We were wrong in thinking the fossil wood would be helpful with understanding the climate.”